Combined ullage rod and breather cap



April 16, 1968 M. P. GASSMAN ETAL. 3,377,708

COMBINED ULLAGE ROD AND BREATHER CAP Filed April 19, 1965 FIG.5

FIG.2

FIG. I-

s RM 0 Tw ms vm mp M J. P. SINGER 77l' 77% ATTORNEY FIG.4

FIG.3

United States Patent O 3,377,708 COMBINED ULLAGE ROD AND BREATHER CAP Max P. Gassman, Waterloo, and John P. Singer, Cedar Falls, Iowa, assignors to Deere & Company, Moline, Ill., a corporation of Delaware Filed Apr. 19, 1965, Ser. No. 448,969 6 Claims. (Cl. B3n-126.7)

ABSTRACT OF THE DISCLOSURE A combined ullage rod and breather cap removably mounted in the access opening of an oil reservoir measures the oil level therein, and has a cap tittable over the access opening and attached to the rod, and further has a handle on the cap exterior by which the rod is rotated to contract or expand a sealing member mounted on the rod and engageable with the walls of the opening loosely or tightly to seal the opening. A filter element is provided between the cap and the sealing member. The latter has a vent passage for venting the oil reservoir through the filter and past the cap to the atmosphere.

This invention relates to a device which measures the liquid level in a container and also functions as a filter cap and breather for the container. More particularly, this invention relates to an improved type of such a device for use on an oil reservoir, such as is found in a tractor transmission, engine crankcase, or hydraulic system.

The oil level in such a reservoir is conventionally measured by an ullage rod or dip stick. It is frequently desirable to vent such containers to the atmosphere toV maintain the container at a relatively constant pressure.' V While it is known to combine a dip stick with a breather type filler cap to accomplish this, previous devices of this type have permitted the introduction of foreign material, such as dust or moisture, into the container.

It is the object of the present invention to provide an improved combination uliage rod and breather type ller cap which prevents the introduction of foreign material into the container, and more particularly, to provide such a device with a filter through which the :container is vented and also to provide such a device with a novel seal which engages the container access opening for secui-ely mounting the device in the opening.

Another object is to provide such a device which is easy to remove and replace in the container, and which is of simple and inexpensive construction.

These and other objects wil become apparent from a consideration of the following detailed description and accompanying drawings wherein:

FIG. l is an elevation View of the combined ullage rod and breather cap.

FIG. 2 is a longitudinal-central section of the ullage rod and breather cap mounted in a conventional cntainer access opening.

FIG. 3 is a section taken along the line 3-3 of FIG. 2.

FIG. 4 is a section taken along the line 4 4 of FIG. 2.

FIG. 5 is a section similar to FIG. 2 showing a slightly diierent embodiment of the invention.

lt is to be understood that such terms as upwardly, downwardly, top, bottomf etc. in the ensuing description are used to more clearly describe the invention, and such terms are not to be construed as limiting the geography or orientation of the components.

A container 10, such as a transmission housing, engine crankcase, or hydraulic system reservoir, is partly shown in FIGS. 2 and 5, and includes an upper wall 11 and an elongated tubular neck portion 12 extending upwardly Cai ICC

from the upper wall 11 and having; a cylindrical inner wall 14 and an annular upper edge 16. The neck portion 12 forms an opening 18 for access to the interior of the container. While the access opening 18 is shown as being formed by the elongated tubular neck portion 12, the access opening could be formed by a relatively short neck portion or by the upper wall of the container.

The combined tillage rod and breather cap 20, shown in FIGS. 1 through 4, includes an inverted cup-shaped cap 22, mounted over the upper edge 16 of the neck lportion 12 and covering the access opening 18. The cap 22 has an exterior surface 24, an interior surface 26, and a plurality of depending lugs 27, which project from the surface of the cap and engage the upper edge 16 to space the cap 22 a relatively short distance above the upper edge, the gap between the cap 22 and the upper edge 16 forming a passage or vent means 2S between the access opening 18 and the atmosphere.

An ulage rod or dip stick extends axially through the cap 22 and the opening 18 into the container interior, the depending lower portion 32 forming an indicator means for measuring the uid level in the container. The exterior portion of the rod 30, above the exterior surface 24 of the cap 22, forms a handle 34 rigidly attached to the cap 22.

A sealing means, indicated generally by the numeral 36, includes a pair of radial members 38, each radial member being formed by a pair of circular plates adjacently mounted on the ullage rod Sil within the neck portion 12, the outer edge of each circular plate 40 having a liared portion 42 directed away from the adjacent plate to form a groove 4.14 around the Outer periphery of cach radial member 38. An annular sealing member 4.6, preferably a rubber O-ring, is mounted in each groove and engages the inner wall 14 of the neck portion 12. While the sealing means 36 is shown to include a pair of radial members 38, a greater or lesser number of radial members and sealing members'could be utilized within the scope of the invention.

Each radial member 38 has a plurality of axially directed apertures 48 forming a passage or Vent means between the opposite sides of the sealing means 36. The apertures 4Sthrough the adjacent radial members 38 are preferably unt-dined to impede the passage of non-gaseous material through the sealing means.

An annular member 50 having a radial opening 52 is coaxially mounted between the cap 22 and the uppermost radial member 38, the aperture 48 through the uppermost radial member 38 communicating with the interior of the annular member S0.

A circular plate 5d, coaxially mounted on the upper edge of the member St), compresses a sealing washer 56 around the rod 3i? against the inner surface of the cap 22 to se'al the connection between the rod and the cap. The washer 56, the plate S4, the annular member 5t), and the radial members 38 are axially stacked around the rod 30 between the cap 22 and a retaining means 58 on the rod 3l), the retaining means 58 being shown as a swagin'g on the rod 3i) which engages the lowermost plate 40.

A filter element 60 is mounted in the interior of the annular member 50 and preferably comprises a mass of corrosion resistant metallic wire, interwoven into a metallic wool, which can be either loosely packed into the annular member interior or supplied in a preshaped pellet substantially conforming to said interior.

When the combined ullage rod and breather cap 29 is installed in the container opening 18, as shown in FIG. 2, it is securely maintained in this position by the sealing means 36, which tightly closes the opening except for the apertures 48. Since the lter element d@ is interposed lbetween the apertures 48 and the vent means 28, gases moving to and from the container interior pass through the filter element 60 for removal of undesirable foreign material. To check the level of fluid in the container or to add iiuid, the entire device Ztl is removed, the liquid level being marked on the indicator portion 32. of the rod 36.

In FIG. 5, there is shown a slightly different embodiment of the invention, mounted in the container It?, and including means for more securely maintaining the device in the access opening 13 of the container 1G; The combined tillage rod land cap 62 again includes an inverted cup-shaped cap 64 having an outer surface 66 and an inner surface `68 and a plurality of depending lugs 70 which space the cap 64 from the upper edge 16 to form a vent means 71.

An ullage rod 72 includes la cylindrical upper portion 74- which extends axially and rotatably through the cap 64 and terminates in a handle 76 on the exterior side of the cap. The rod 72 also includes a threaded portion 78 on the interior side of the cap 64 and a depending indicator portion Si?, which extends into the container interior for indicating the level of liquid in the container. The rod 72 extends through a rotary seal 82 mounted on the cap 64 for sealing the connection between the rod and the cap and maintaining the axial position of the rod relative to the cap.

A sealing means 83 includes two pair of circularplates 84 coaxially rotatable and axially and unthreadably movable on the threaded portion 7S. Each plate has a flared portion 8S at its outer periphery, the flare on adjacent plates being in opposite directions so that each pair of plates 84 forms a peripheral groove 90. An annular sealing member 92, preferably a resilient O-ring, is mounted in each groove 90 and engages the side wall 14.

An annular spacer 93 is coaxially mounted around the rod 72 between the upper most circular plate Sli and the interior surface `63 of the cap `54. A sleeve nut 9A; is aflixed to and depends from the lowermost plate 8.4 and is threadably mounted on the threaded portion 7S of the rod 72 for axial movement, in response to rotation of the rod, between a first or lower position against a stop means 96 mounted on the rod and a second or upper position wherein the spacer 93 and the stacked plates 84 are compressed to their solid height. In the first position, there is an axial spacing between the opposite plates in each pair of plates, whereby the effective circumference of the peripheral groove 90 is reduced so that each O-ring only lightly engages the wall 14. As the handle 76 is rotated, the circular plates 8d and the sleeve nut 94 are prevented from rotating, since the O-rings 92 engage the wall 14, and the sleeve nut 94 moves upwardly away from the stop means 96 toward its second position, increasing the effective circumference of the groove 90 and forcing each O-ring into a tighter engagement against the wall 14. When the sleeve nut 9d reaches its second position, the access opening 1S is tightly closed, and the device is securely mounted in said opening.

To incorporate thet filtered breathing feature of the device 72, each circular plate 84 is again provided with a plurality of axially directed apertures 9S, and the sleeve nut 94- is provided with an aperture 16)@ alined with the lowermost aperture 98, connecting the interior of the container to the interior of the spacer 93. The annular spacer 93 has a radial slot or opening 162 for connecting the interior of the spacer to the atmosphere via the vent means 71. A filter element 104` is mounted in the interior of the spacer 93 between the apertures 98 and the opening 162 and vent means 71, whereby gases moving to and from the container interior must pass through the filter element 104 for removal of undesirable materials.

Other features and advantages of the present invention will readily occur to those skilled in the art, as will many modifications and alterations in the preferred embodiment of the invention described herein, all of whith may be achieved without departing from the spirit and the scope of the invention.

What is claimed is:

1. In a container adapted to contain fluid at a predetermined level and having an upwardly disposed circular opening for access to the container interior, a combined closure and ulla-ge device removably mounted in said opening and comprising: a cap removably mounted over said opening; an ullage rod rotatably extending through said cap in an axial direction relative to said opening, the ullage rod having a handle portion on the exterior side of said cap, a threaded portion on the interior side of said cap, and a depending indicator portion for measuring the uid level in the container; at least one pair of adjacent circular plates coaxially mounted in said container opening, and unthreadably rotatable and axially movable on said rod between a first position wherein they are axially spaced and a second position wherein they are axially compressed, each plate being iiared at its outer periphery to form a peripheral groove; an O-ring of resilient material mounted in each peripheral groove and engaging the wall of said container opening; 'a spacer means mounted between the cap and the uppermost circular plate for spacing the uppermost plate from the cap; a sleeve nut threadably mounted on the threaded portion of the rod and attached to the lowermost circular plate for axial movement along the rod in response to rotation of the rod between a first position, wherein each pair of plates is allowed to axially separate to its first position to decrease the effective circumference of the peripheral groove so that each Oring lightly engages the opening wall, and a second position, wherein the sleeve nut axially compresses the plates against the spacer means into their second position to hold their solid yaxial dimension, increasing the effective circumference of the groove and compressing each O-ring tightly against the wall.

2. The invention defined in claim 1 wherein the first position of the sleeve nut is established by a stop means mounted on the rod.

3. The invention defined in claim 1 wherein the cap includes a first vent means connecting the cap interior to the atmosphere, and the spacer means includes an annular member around the rod having an opening for connecting the annular member interior to the first vent means, and the circular plates and the sleeve nut form a second vent means between the container interior and the annular member interior, Iand including a filter element mounted in the annular member interior between the rst and second vent means.

4. In a container adapted to contain tiuid at a predetermined level and having an upwardly disposed circular opening with a cylindrical wall for access to the container interior, the combination therewith of a combined closure, venting, and ulla'ge device removably mounted in said opening and comprising: a cap removably mounted over said opening; an elongated ullage rod depending from the cap, axially extending through the container opening into the container interior and coaxially rotatable relative to the walls of the opening when the cap is mounted over said opening; at least one sealing member having a generally circular cross-section coaxially mounted on and rotatable relative to the ullage rod, and including a resilient, radially expandable annular sealing element coaxially disposed on its periphery and engageable with the walls of the opening when the device is mounted in the opening, said sealing member substantially closing the opening and being shiftable between an axially expanded, radially contracted condition wherein the sealing element lightly engages the wall of the opening and an axially compressed radially expanded condition wherein the sealing element is deformably compressed against the wall; means mounted on the ullage rod and operatively connecting the rod and the Sealing member to shift the sealing member between its alternate conditions; a rst vent means operatively associated with the cap for venting the cap interior to atmosphere; and a second vent means through the sealing member and operative to vent the container interior to the cap interior; the ullage rod including a threaded portion and the sealing member being unthreadably rotatable and axially shiftable on the threaded portion, and the connecting means including a sleeve nut non-rotatably engageable with the sealing member and threadably rotatable on the threaded portion of the rod for axial shifting in response to rotation of the ullage rod.

5. The invention defined in claim 4 and including a gas-permeable lilter means between the first vent means and the second vent means for filtering gas moving through the vent means, between the container interior and the atmosphere.

6. The invention dened in claim 4 wherein the sealing member includes a pair of adjacent circular plates axially shiftable and unthreadably rotatable on the threaded portion of the rod and axially shiftable relative to each other, the outer periphery of the respective plates being ared in opposite directions to form. a peripheral groove, the effective diameter of which increases or decreases as the plates respectively move axially toward and away from each other, the sleeve nut `being attached to the lower plate for shifting said plate toward and away from the opposite plate in response to rotation of the rod, and the sealing element includes an O-ring of resilient material coaxially mounted in said groove.

References Cited UNITED STATES PATENTS 2,032,800 3/ 1936 Haltenberger 3x3-126.7 2,096,358 10/1937 Gautier u 220-24.5 3,296,703 1/1967 Stade et al. 33--126.7

LEONARD FORMAN, Primary Examiner. R. A. FIELDS, Assistant Examiner. 

